The disclosure relates to a method for correcting a compensation item of a permanent magnet synchronous motor (PMSM).
The air blowers are driven by a PMSM motor, and the rotation speed of the motor is controlled by a motor controller.
When the motor controller is working, to avoid the simultaneous turn-on/off of the switching transistors of the upper and lower half bridges of a frequency inverter, it is necessary to set a deadzone time; however, this inevitably leads to an error (in industry, it is called a deadzone error) between a given command voltage and an output voltage; therefore, during operation, the motor controller requires an appropriate compensation to correct the error.
In addition, in production, the operating parameters of the motor tend to fluctuate; if the fluctuation deviations are not corrected, the control accuracy of the motor controller will decrease, adversely affecting the performance of the motor.
So far, a common method for determining the compensation value for correcting the error is to use a reference model to calculate the compensation value prior to mass production. However, the method is a theoretical one-time correcting method, and cannot compensate errors in the operation processes.
Another method for determining the compensation value for correcting the error is to use additional pins on a Microprogram Control Unit (MCU) to real-time calculate a no-load time. This method requires at least 3 additional MCU pins. However, the method introduces extra hardware, which increases new potential fault point, reducing the reliability of the entire system.